THE REGION OF THE ANKLE AND FOOT 477 



consequently more liable to injury in these areas. When the 

 epiphyseal cartilage is affected and it is feared that shortening 

 of the tibia will result, subsequent inversion of the foot may be 

 obviated by fracturing the fibula and allowing the ends to 

 overlap. 



In the Surgical Approach to the Fibula the incisions 

 are planned to avoid injuring the superficial peroneal (musculo- 

 cutaneous) nerve. Subperiosteal resection of the proximal or 

 middle thirds is carried out through an incision along the line 

 of the posterior intermuscular septum. In the proximal third 

 the wound is deepened between the adjoining borders of the 

 soleus and the peronseus longus, and care must be taken not 

 to injure the common peroneal nerve as it winds round the 

 fibular neck. 



In the middle third, the incision exposes the peronseus longus 

 in front and the flexor hallucis longus behind, the latter muscle 

 projecting from under cover of the lateral border of the soleus. 



In the distal third, the incision lies just posterior to the anterior 

 intermuscular septum, and the periosteum is divided between 

 the peronseus brevis and the peronseus tertius. 



Fractures of the Leg may involve one or both bones. 

 When only one bone is fractured there is little displacement, 

 and the sound bone acts as a satisfactory support. 



Both bones may be fractured as the result of direct or indirect 

 violence. In the former case the fractures are transverse and 

 occur at the same level in both bones. In indirect violence the 

 bones give way at different levels, the tibia at the junction of its 

 middle and distal thirds, and the fibula at the junction of its 

 middle and proximal thirds. When displacement occurs, it is 

 due to the powerful triceps suras, which draws the distal 

 fragments upwards behind the proximal fragments and often 

 causes some degree of anterior angulation. 



As the medial surface of the tibia is covered only by skin 

 and superficial fascia, fractures of this bone are not uncommonly 

 compound. 



THE REGION OF THE ANKLE AND FOOT. 



Surface Landmarks. The twomalleoli serve as important 

 guides to the surgeon in operations in the region of the ankle- 

 joint. The lateral malleolus is the larger of the two, and its tip 



